Push to talk calls generally use a forced-audio model where the user of the receiver mobile station (“MS”) does not have to answer the call in order to set up the call. Since push to talk technology includes dispatch calls, “push to talk,” as used herein, shall be understood to serve as an expression of convenience that encompasses various kinds of push to talk communications including networks that employ a dispatcher and those that do not. Because of this configuration of push to talk calls, the user of the receiver MS may miss the audio message of the push to talk call, because the MS may be inaccessible (e.g., the MS is in the user's pocket and/or the user is away from the MS) to provide for clear audio output. In this scenario, the user of the receiver MS may hear a noise that indicates a call coming in but may be unable to make out the actual call message, which would likely generate unnecessary follow up push to talk calls between the sender and receiver to clarify the previously made call message.
This uncertainty and lack of clarity not only unnecessarily wastes transmission resources but also degrades user experience. In the worst case scenario, the user may not know at all that a push to talk call was received until the phone log is checked. There may also be circumstances where certain factors (e.g., background noise and/or interference) may hinder the audio reception, resulting in unreliable audio outputs. Unreliable push to talk audio data messages become especially critical when the calls are exchanged in a dispatcher emergency setting where time is of the essence and wrong information can be fatal.
Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help improve understanding of various embodiments of the present invention. Also, common and well-understood elements that are useful or necessary in a commercially feasible embodiment are often not depicted in order to facilitate a less obstructed view of these various embodiments of the present invention.